1 files changed, 42 insertions, 32 deletions

diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index db813f819ad6..884b88e25141 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -45,7 +45,21 @@ static u64 prefetch_disable_bits;
  */
 static unsigned int pseudo_lock_major;
 static unsigned long pseudo_lock_minor_avail = GENMASK(MINORBITS, 0);
-static struct class *pseudo_lock_class;
+
+static char *pseudo_lock_devnode(const struct device *dev, umode_t *mode)
+{
+	const struct rdtgroup *rdtgrp;
+
+	rdtgrp = dev_get_drvdata(dev);
+	if (mode)
+		*mode = 0600;
+	return kasprintf(GFP_KERNEL, "pseudo_lock/%s", rdtgrp->kn->name);
+}
+
+static const struct class pseudo_lock_class = {
+	.name = "pseudo_lock",
+	.devnode = pseudo_lock_devnode,
+};
 
 /**
  * get_prefetch_disable_bits - prefetch disable bits of supported platforms
@@ -420,6 +434,7 @@ static int pseudo_lock_fn(void *_rdtgrp)
 	struct pseudo_lock_region *plr = rdtgrp->plr;
 	u32 rmid_p, closid_p;
 	unsigned long i;
+	u64 saved_msr;
 #ifdef CONFIG_KASAN
 	/*
 	 * The registers used for local register variables are also used
@@ -463,6 +478,7 @@ static int pseudo_lock_fn(void *_rdtgrp)
 	 * the buffer and evict pseudo-locked memory read earlier from the
 	 * cache.
 	 */
+	saved_msr = __rdmsr(MSR_MISC_FEATURE_CONTROL);
 	__wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);
 	closid_p = this_cpu_read(pqr_state.cur_closid);
 	rmid_p = this_cpu_read(pqr_state.cur_rmid);
@@ -475,7 +491,7 @@ static int pseudo_lock_fn(void *_rdtgrp)
 	 * pseudo-locked followed by reading of kernel memory to load it
 	 * into the cache.
 	 */
-	__wrmsr(IA32_PQR_ASSOC, rmid_p, rdtgrp->closid);
+	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, rdtgrp->closid);
 	/*
 	 * Cache was flushed earlier. Now access kernel memory to read it
 	 * into cache region associated with just activated plr->closid.
@@ -511,10 +527,10 @@ static int pseudo_lock_fn(void *_rdtgrp)
 	 * Critical section end: restore closid with capacity bitmask that
 	 * does not overlap with pseudo-locked region.
 	 */
-	__wrmsr(IA32_PQR_ASSOC, rmid_p, closid_p);
+	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, closid_p);
 
 	/* Re-enable the hardware prefetcher(s) */
-	wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0);
+	wrmsrl(MSR_MISC_FEATURE_CONTROL, saved_msr);
 	local_irq_enable();
 
 	plr->thread_done = 1;
@@ -565,7 +581,7 @@ static int rdtgroup_locksetup_user_restrict(struct rdtgroup *rdtgrp)
 	if (ret)
 		goto err_cpus;
 
-	if (rdt_mon_capable) {
+	if (resctrl_arch_mon_capable()) {
 		ret = rdtgroup_kn_mode_restrict(rdtgrp, "mon_groups");
 		if (ret)
 			goto err_cpus_list;
@@ -612,7 +628,7 @@ static int rdtgroup_locksetup_user_restore(struct rdtgroup *rdtgrp)
 	if (ret)
 		goto err_cpus;
 
-	if (rdt_mon_capable) {
+	if (resctrl_arch_mon_capable()) {
 		ret = rdtgroup_kn_mode_restore(rdtgrp, "mon_groups", 0777);
 		if (ret)
 			goto err_cpus_list;
@@ -736,7 +752,7 @@ int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
 	 * anymore when this group would be used for pseudo-locking. This
 	 * is safe to call on platforms not capable of monitoring.
 	 */
-	free_rmid(rdtgrp->mon.rmid);
+	free_rmid(rdtgrp->closid, rdtgrp->mon.rmid);
 
 	ret = 0;
 	goto out;
@@ -760,8 +776,8 @@ int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp)
 {
 	int ret;
 
-	if (rdt_mon_capable) {
-		ret = alloc_rmid();
+	if (resctrl_arch_mon_capable()) {
+		ret = alloc_rmid(rdtgrp->closid);
 		if (ret < 0) {
 			rdt_last_cmd_puts("Out of RMIDs\n");
 			return ret;
@@ -771,7 +787,7 @@ int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp)
 
 	ret = rdtgroup_locksetup_user_restore(rdtgrp);
 	if (ret) {
-		free_rmid(rdtgrp->mon.rmid);
+		free_rmid(rdtgrp->closid, rdtgrp->mon.rmid);
 		return ret;
 	}
 
@@ -828,6 +844,9 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d)
 	struct rdt_domain *d_i;
 	bool ret = false;
 
+	/* Walking r->domains, ensure it can't race with cpuhp */
+	lockdep_assert_cpus_held();
+
 	if (!zalloc_cpumask_var(&cpu_with_psl, GFP_KERNEL))
 		return true;
 
@@ -835,7 +854,7 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d)
 	 * First determine which cpus have pseudo-locked regions
 	 * associated with them.
 	 */
-	for_each_alloc_enabled_rdt_resource(r) {
+	for_each_alloc_capable_rdt_resource(r) {
 		list_for_each_entry(d_i, &r->domains, list) {
 			if (d_i->plr)
 				cpumask_or(cpu_with_psl, cpu_with_psl,
@@ -871,6 +890,7 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_domain *d)
 static int measure_cycles_lat_fn(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
+	u32 saved_low, saved_high;
 	unsigned long i;
 	u64 start, end;
 	void *mem_r;
@@ -879,6 +899,7 @@ static int measure_cycles_lat_fn(void *_plr)
 	/*
 	 * Disable hardware prefetchers.
 	 */
+	rdmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
 	wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);
 	mem_r = READ_ONCE(plr->kmem);
 	/*
@@ -895,7 +916,7 @@ static int measure_cycles_lat_fn(void *_plr)
 		end = rdtsc_ordered();
 		trace_pseudo_lock_mem_latency((u32)(end - start));
 	}
-	wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0);
+	wrmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
 	local_irq_enable();
 	plr->thread_done = 1;
 	wake_up_interruptible(&plr->lock_thread_wq);
@@ -940,6 +961,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
 	u64 hits_before = 0, hits_after = 0, miss_before = 0, miss_after = 0;
 	struct perf_event *miss_event, *hit_event;
 	int hit_pmcnum, miss_pmcnum;
+	u32 saved_low, saved_high;
 	unsigned int line_size;
 	unsigned int size;
 	unsigned long i;
@@ -973,6 +995,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
 	/*
 	 * Disable hardware prefetchers.
 	 */
+	rdmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
 	wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);
 
 	/* Initialize rest of local variables */
@@ -1031,7 +1054,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
 	 */
 	rmb();
 	/* Re-enable hardware prefetchers */
-	wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0);
+	wrmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high);
 	local_irq_enable();
 out_hit:
 	perf_event_release_kernel(hit_event);
@@ -1347,7 +1370,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 					    &pseudo_measure_fops);
 	}
 
-	dev = device_create(pseudo_lock_class, NULL,
+	dev = device_create(&pseudo_lock_class, NULL,
 			    MKDEV(pseudo_lock_major, new_minor),
 			    rdtgrp, "%s", rdtgrp->kn->name);
 
@@ -1377,7 +1400,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 	goto out;
 
 out_device:
-	device_destroy(pseudo_lock_class, MKDEV(pseudo_lock_major, new_minor));
+	device_destroy(&pseudo_lock_class, MKDEV(pseudo_lock_major, new_minor));
 out_debugfs:
 	debugfs_remove_recursive(plr->debugfs_dir);
 	pseudo_lock_minor_release(new_minor);
@@ -1418,7 +1441,7 @@ void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp)
 
 	pseudo_lock_cstates_relax(plr);
 	debugfs_remove_recursive(rdtgrp->plr->debugfs_dir);
-	device_destroy(pseudo_lock_class, MKDEV(pseudo_lock_major, plr->minor));
+	device_destroy(&pseudo_lock_class, MKDEV(pseudo_lock_major, plr->minor));
 	pseudo_lock_minor_release(plr->minor);
 
 free:
@@ -1554,16 +1577,6 @@ static const struct file_operations pseudo_lock_dev_fops = {
 	.mmap =		pseudo_lock_dev_mmap,
 };
 
-static char *pseudo_lock_devnode(struct device *dev, umode_t *mode)
-{
-	struct rdtgroup *rdtgrp;
-
-	rdtgrp = dev_get_drvdata(dev);
-	if (mode)
-		*mode = 0600;
-	return kasprintf(GFP_KERNEL, "pseudo_lock/%s", rdtgrp->kn->name);
-}
-
 int rdt_pseudo_lock_init(void)
 {
 	int ret;
@@ -1574,21 +1587,18 @@ int rdt_pseudo_lock_init(void)
 
 	pseudo_lock_major = ret;
 
-	pseudo_lock_class = class_create(THIS_MODULE, "pseudo_lock");
-	if (IS_ERR(pseudo_lock_class)) {
-		ret = PTR_ERR(pseudo_lock_class);
+	ret = class_register(&pseudo_lock_class);
+	if (ret) {
 		unregister_chrdev(pseudo_lock_major, "pseudo_lock");
 		return ret;
 	}
 
-	pseudo_lock_class->devnode = pseudo_lock_devnode;
 	return 0;
 }
 
 void rdt_pseudo_lock_release(void)
 {
-	class_destroy(pseudo_lock_class);
-	pseudo_lock_class = NULL;
+	class_unregister(&pseudo_lock_class);
 	unregister_chrdev(pseudo_lock_major, "pseudo_lock");
 	pseudo_lock_major = 0;
 }